RESUMO
The research assessed the exposure to total mercury (THg), lead (Pb), and arsenic (As) in Colombian wetland species of different trophic levels Platalea ajaja, Dendrocygna autumnalis and Nannopterum brasilianus. The results show high THg blood levels in P. ajaja (811.00 ± 349.60 µg L-1) and N. brasilianus (209.50 ± 27.92 µg L-1) with P. ajaja possibly exhibiting adverse effects. Blood Pb concentration was high in D. autumnalis (212.00 ± 208.10 µg L-1) and above the threshold for adverse effects, suggesting subclinical poisoning. Levels of blood As were below the assumed threshold for detrimental effect (20 µg L-1). The mean concentration of feather THg was below the assumed natural background levels (5 µg g-1) for all three species. Feather Pb levels exceeded the levels for assumed threshold effects in all sampled N. brasilianus (7.40 ± 0.51 µg g-1). Results for feather As concentration were below the threshold for adverse impacts in all species, although a positive correlation between As and THg concentrations was detected in P. ajaja feathers. The overall results could help understand how metal(loid)s biomagnify through trophic levels and how wetland species may serve as environmental indicators. By exploring the interactions of metal(loid)s within different matrices and body, this study offers insights into the dynamics of contaminant accumulation and distribution in the environment. This concept can be applied to wetlands worldwide, where bird species can serve as indicators of ecosystem health and the presence of contaminants such as heavy metals and metalloids.
Assuntos
Aves , Monitoramento Ambiental , Plumas , Chumbo , Metais Pesados , Áreas Alagadas , Animais , Plumas/química , Chumbo/sangue , Poluentes Químicos da Água , Arsênio , Mercúrio/sangue , Colômbia , Poluentes Ambientais/sangueRESUMO
Measuring stable isotopes in different tissues offers the opportunity to provide insight into the foraging ecology of a species. This study aimed to assess how diet varies between yellow females, yellow males, and dull individuals of a Saffron Finch (Sicalis flaveola) population. We measured δ13C and δ15N in blood over a year, and in different feathers, to estimate seasonal consistency of resource use for each category. We conducted this study in a private farm in the Central Brazilian savannas. We sampled 195 individuals in seven field samplings between January 2017 and March 2018. The mean blood δ13C values were similar among yellow females, yellow males and dull individuals, indicating that this population of Saffron Finch predominantly accesses similar resources throughout the year, with a predominant C4 signal. Although Saffron Finch is considered a granivorous species, the mean δ15N values found indicate that both adults and juveniles also incorporate in their tissues some invertebrate. The slight isotope-tissue difference between feathers and blood is similar to the reported in previous studies and may reflect tissue-to-tissue discrimination. The isotopic space of yellow males was greater than that of yellow females and dull individuals, indicating greater dietary diversity due to greater inter-individual variation in diet. In Saffron Finch, which delays plumage maturation, competition-driven partitioning of food resources seems essential in driving carotenoid-based plumage coloration between age classes and sexes.
Assuntos
Isótopos de Carbono , Dieta , Plumas , Comportamento Alimentar , Tentilhões , Isótopos de Nitrogênio , Estações do Ano , Animais , Feminino , Masculino , Tentilhões/fisiologia , Plumas/química , Dieta/veterinária , Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Comportamento Alimentar/fisiologia , Fatores Sexuais , Fatores Etários , BrasilRESUMO
How does sexual selection impact introgression dynamics across a hybrid zone? Long et al. (2024) used historical (1989-1994) and contemporary (2017-2020) samples to quantify the stability of a Panamanian hybrid zone between golden-collared manakins (Manacus vitellinus) and white-collared manakins (M. candei). Their analyses revealed a spatially stable hybrid zone, except for one trait, belly plumage coloration, which has introgressed into the distribution of the white-collared manakin. This finding suggests possible sexual selection for this trait.
Assuntos
Hibridização Genética , Passeriformes , Pigmentação , Animais , Panamá , Pigmentação/genética , Passeriformes/genética , Passeriformes/fisiologia , Plumas , Introgressão Genética , Masculino , Seleção SexualRESUMO
Birds are good bioindicators of disturbance in the environment. They are present in different habitats and trophic levels. In addition, rapid urbanization has led birds to use cities as shelter and for seeking food resources. Sewage treatment plants (STPs) are suitable locations for free-living birds within cities. However, few studies address the impacts of emerging pollutants from sewage treatment plants on wild birds. In this sense, the aim of this study was to analyze the genotoxic, mutagenic, and immunological impacts from metal and pollutant exposure on free-living birds collected at a STP. For comparison, birds were collected in a preserved environment, the Silvania National Forest (FLONA). To achieve this, we used non-destructive biomarkers sensitive to environmental changes. Birds were collected in both environments using mist nets. After collection, birds were weighed, measured, species-identified, and released. Blood was collected for comet assay, micronucleus test, and leukocyte profile, while feathers were collected for metal concentration analysis. Water physicochemical parameters were measured at both sites, and water samples were collected for metal analysis. Our results demonstrated that birds collected at the STP exhibit a higher frequency of genotoxic damage and erythrocyte abnormalities, and increased immune response compared to FLONA birds. Traces of potentially toxic metals, such as Hg and As, were found in the birds feathers from both environments, raising concerns about metal contamination in both environments. Trophic guilds appear to respond similarly to exposure. The parameters and metals found in the water reflect environmental characteristics and may be influencing pollutant availability. Finally, despite the advancement of our findings, studies linking these damages to detrimental effects on behavior and reproduction are encouraged.
Assuntos
Biomarcadores , Aves , Urbanização , Animais , Biomarcadores/sangue , Monitoramento Ambiental/métodos , Testes para Micronúcleos , Ensaio Cometa , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Esgotos , Brasil , Metais/análise , Metais/toxicidade , Dano ao DNA , Plumas/química , EcotoxicologiaRESUMO
Artisanal and Small-Scale Gold Mining (ASGM) represents a significant source of anthropogenic mercury emissions to the environment, with potentially severe implications for avian biodiversity. In the Madre de Dios department of the southern Peruvian Amazon, ASGM activities have created landscapes marred by deforestation and post-mining water bodies (mining ponds) with notable methylation potential. While data on Hg contamination in terrestrial wildlife remains limited, this study measures Hg exposure in several terrestrial bird species as bioindicators. Total Hg (THg) levels in feathers from birds near water bodies, including mining ponds associated with ASGM areas and oxbow lakes, were analyzed. Our results showed significantly higher Hg concentrations in birds from ASGM sites with mean ± SD of 3.14 ± 7.97 µg/g (range: 0.27 to 72.75 µg/g, n = 312) compared to control sites with a mean of 0.47 ± 0.42 µg/g (range: 0.04 to 1.89 µg/g, n = 52). Factors such as trophic guilds, ASGM presence, and water body area significantly influenced feather Hg concentrations. Notably, piscivorous birds exhibited the highest Hg concentration (31.03 ± 25.25 µg/g, n = 12) exceeding known concentrations that affect reproductive success, where one measurement of Chloroceryle americana (Green kingfisher; 72.7 µg/g) is among the highest ever reported in South America. This research quantifies Hg exposure in avian communities in Amazonian regions affected by ASGM, highlighting potential risks to regional bird populations.
Assuntos
Aves , Monitoramento Ambiental , Ouro , Mercúrio , Mineração , Animais , Mercúrio/análise , Peru , Plumas/química , Poluentes Químicos da Água/análise , Poluentes Ambientais/análise , Exposição AmbientalRESUMO
Antarctica is the most remote and coldest regions of the planet, but the presence of REEs there has received little attention. This study assessed REE-contents in the feathers of adult gentoo penguins from Ardley Island, Kopaitic Island and Base O'Higgins. Field work was accomplished during 2011 (austral summer), and determination of elements was performed with ICP-MS. In general, REE-levels showed descending relations as follows: Ce > La > Y > Nd > Sc > Pr > Gd > Sm > Dy >Er > Yb > Eu > Ho > Tb > Tm > Lu. The data showed an increase of the levels of REEs from the lower part of the feather to the tip. This finding seems to be spatially dependent, but geochemical, anthropogenic conditions, feeding habits, sex, or even health status of birds should also be considered. It is a subject that requires deeper attention in future studies.
Assuntos
Metais Terras Raras , Spheniscidae , Animais , Regiões Antárticas , PlumasRESUMO
Landfills are sources of soil, water, and air pollution due to the release of toxic compounds such as metals and metalloids. In both tropical and temperate environments, scavenger birds such as the Black Vulture (Coragyps atratus) that have learned to use these sites as a feeding area are probably exposed to metals, metalloids and other "persistent bioaccumulative toxic substances (PBTs)" released in open dumpsite (OD) and sanitary landfill (SL). The objective of this study is to evaluate the presence and distribution of toxic metals (Al, Sn, Hg, Cu, Pb, Cd, Cr) and As in OD and SL from urban, semi-urban and rural localities in Campeche, México, using molting feathers of C. atratus as bioindicators. A total of 125 Black Vulture primary and secondary wing feathers were collected from OD and SL. Metals were determined by voltammetry through acid digestion. The highest levels of metals occurred in landfills in urban, semi-urban, and rural localities. The elements with the highest concentrations were Al, with an average of 35.67 ± 33.51 µg g-1 from rural environments, and As, with 16.20 ± 30.06 µg g-1 from the urban localities. Mercury was the only element that had a very homogeneous distribution between the three environments we studied. In general, Pb, Hg, Cu and Cd were the elements that presented the lowest concentrations with 0.32 ± 0.35, 0.16 ± 0.22, 0.14 ± 0.31 and 0.06 ± 0.10 µg g-1, respectively regardless of any particular location or environment. Black Vultures from dumpsites are good bioindicators of what humans consume in urban, semi-urban, and rural environments. However, the conservation of vultures is of great importance since these scavenger birds perform ecosystem services by feeding on decomposing organic material.
Assuntos
Falconiformes , Mercúrio , Metaloides , Metais Pesados , Humanos , Animais , Biomarcadores Ambientais , Metaloides/análise , Ecossistema , Cádmio , Plumas , México , Chumbo , Monitoramento Ambiental , Aves , Metais Pesados/análiseRESUMO
Monitoring of contaminant levels in wildlife over time is a tool for assessing the presence and persistence of environmental impacts at ecosystem, community and population levels. Tropical seabirds breeding in the Abrolhos Archipelago, 70 km off the Brazilian coast, forage in areas under the influence of the Doce River discharge. In 2015, the Fundão Dam collapsed and released ca 60 million tons of iron ore tailings into the ocean. In the present study, red-billed tropicbirds Phaethon aethereus and brown boobies Sula leucogaster breeding in Abrolhos were monitored over four years (2019-2022) for metal (Fe, Mn, Zn, Cu, Cr, Hg, Pb, Cd) and metalloid (As) concentrations in blood and feathers. Over six sampling events, metal (loid) concentrations showed strong temporal variation in both tissues. Overall, feathers showed greater element concentrations than blood, with stronger correlations between elements, especially Mn and the nonessential As, Cd, Hg and Pb. Mn is one of the major chemical markers of the Fundão Dam tailings. Metal (loid) concentrations in the tropical seabirds evaluated were above suggested threshold levels for most nonessential elements (As, Cd and Pb), especially in February 2021, when metal (loid) concentrations peaked in feathers. In this case, values were orders of magnitude higher than those observed in other sampling events. This occurred one year after a major rainy season in the Doce River basin, which increased river discharge of contaminated mud into the ocean, where contaminants are further remobilized by winds and currents, resulting in transference through the marine food web. This finding is consistent to what has been observed for other ecosystem compartments monitored in the region under the influence of the Doce River. Our findings highlight the utility of using tropical seabirds as sentinels of marine pollution, revealing strong temporal patterns in metal (loid) concentrations associated to bottom-up climatic processes.
Assuntos
Arsênio , Desastres , Mercúrio , Poluentes Químicos da Água , Animais , Arsênio/análise , Ecossistema , Plumas , Cádmio , Chumbo , Monitoramento Ambiental/métodos , Aves , Brasil , Rios , Poluentes Químicos da Água/análiseRESUMO
This study investigated the feathers' composition of South polar skua (Stercorarius maccormicki) using WDXRF, evaluating the concentration of essential and non-essential elements in the feathers, and dividing it into rachis and barb parts. We collected South polar skuas feathers from Hennequin Point, King George Island, South Shetland, Antarctic Peninsula in January of 2013. Our results show that 18 elements were observed in the composition of the feathers, with a different concentration between the rachis and barbs, qualitatively and quantitatively. Only 3 elements observed were classified as non-essentials but still mostly elements do not have a function described in the literature to the feathers. According to our knowledge, this is the first study that uses this technique to evaluate the concentration of different elements in the feathers. The findings of this study highlight the use of alternative techniques to biomonitoring elements in the ecosystem and bring baseline information for future studies.
Assuntos
Charadriiformes , Ecossistema , Animais , Plumas , Regiões Antárticas , Monitoramento BiológicoRESUMO
Urbanization stands out as a significant anthropogenic factor, exerting selective pressures on ecosystems and biotic components. A notable outcome of urbanization is thermal heterogeneity where the emergence of Urban Heat Islands is characterized by elevated air and surface temperatures compared to adjacent rural areas. Investigating the influence of thermal heterogeneity on urban animals could offer insights into how temperature variations can lead to phenotypic shifts. Urban pigeons (Columba livia) serve as an excellent model for studying urban thermal effects, given the melanism variations, which are associated with the pleiotropy of the melanocortin system. To examine the development of physiological plasticity in response to urban thermal variations, we conducted a study on pigeons in Santiago, Chile, during the rainy season. We assessed the influence of habitat on physiological traits related to metabolism and antioxidant capacities, which are theoretically affected by feather coloration. Our findings reveal that variations in melanism significantly impact pigeon physiology, affecting both antioxidant capacities and the mitochondrial activity of red blood cells. It was found that higher urban temperatures, from both the current sampling month and the prior sampling month (from CRU TS dataset), were negatively and strongly associated with lower antioxidant and metabolic activities. This suggests that elevated urban temperatures likely benefit the energetic budgets of pigeon populations and mitigate the negative effects of oxidative metabolism, with differential effects depending on feather colorations.
Assuntos
Columbidae , Melanose , Animais , Columbidae/fisiologia , Cidades , Plumas , Antioxidantes , Ecossistema , Temperatura Alta , Estresse OxidativoRESUMO
Patagonia is one of the last pristine regions on the southern hemisphere. The impact of rare earth element (REEs) and trace elements (TEs) in this region have received little attention. The main goal was to assess REEs burden in feathers of adult magellanic penguins (Spheniscus magellanicus). Sampling was performed at Magdalena Island of the Chilean Patagonia during the austral summer of 2011. Multi-elemental determination of 16 REEs and 24 TEs was performed with ICP-MS. The levels of REEs, TEs, and stable isotopes (δ15N, δ13C, and δ34S) were measured to assess the factors that condition the avian exposure to environmental contaminants. The results showed an increase of the levels of REEs and TEs from the calamus to the feather's tip. In the whole feather, the highest levels corresponded to Ce, which exhibited more than two order of magnitude than Lu and Tm levels. Similar to other penguin species, magellanic penguins can be vectors of REEs and metals in remote regions. Stable isotopes revealed that trophic ecology may influence some of the element concentrations in feathers of magellanic penguins, an issue that requires deeper attention.
Assuntos
Metais Terras Raras , Spheniscidae , Oligoelementos , Animais , Oligoelementos/análise , Plumas/química , ChileRESUMO
Mercury (Hg) contamination remains a significant environmental concern. In aquatic ecosystems, Hg can undergo methylation, forming its organic form, methylmercury (MeHg), which bioaccumulates and biomagnifies in the food chain, ultimately reaching the top predators, including waterfowl. The objective of this study was to investigate the distribution and levels of Hg in wing feathers, with a specific focus on evaluating heterogeneity in the primary feathers of two kingfisher species (Megaceryle torquata and Chloroceryle amazona). The concentrations of total Hg (THg) in the primary feathers of C. amazona individuals from the Juruena, Teles Pires, and Paraguay rivers were 4.724 ± 1.600, 4.003 ± 1.532, and 2.800 ± 1.475 µg/kg, respectively. The THg concentrations in the secondary feathers were 4.624 ± 1.718, 3.531 ± 1.361, and 2.779 ± 1.699 µg/kg, respectively. For M. torquata, the THg concentrations in the primary feathers from the Juruena, Teles Pires, and Paraguay rivers were 7.937 ± 3.830, 6.081 ± 2.598, and 4.697 ± 2.585 µg/kg, respectively. The THg concentrations in the secondary feathers were 7.891 ± 3.869, 5.124 ± 2.420, and 4.201 ± 2.176 µg/kg, respectively. The percentage of MeHg in the samples increased during THg recovery, with an average of 95% in primary feathers and 80% in secondary feathers. It is crucial to comprehend the current Hg concentrations in Neotropical birds to mitigate potential toxic effects on these species. Exposure to Hg can lead to reduced reproductive rates and behavioral changes, such as motor incoordination and impaired flight ability, ultimately resulting in population decline among bird populations.
Assuntos
Amazona , Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Humanos , Animais , Mercúrio/análise , Ecossistema , Plumas/química , Paraguai , Monitoramento Ambiental , Aves , Poluentes Químicos da Água/análiseRESUMO
Mercury is a global contaminant found in the Amazon; it can be biomagnified in the aquatic trophic chain. The use of piscivorous birds for biomonitoring of mercury contamination is increasing, mainly due to the non-mobility of mercury in bird feathers. We examined the concentrations of total mercury and methylmercury in different tissues of the green kingfisher, Chloroceryle americana collected from the Teles Pires and Juruena Rivers in the southern Brazilian Amazon. We also evaluated total mercury in small Characidae fish (potential C. americana food) in the same areas. The results indicate contamination of the birds with high concentrations, on average two-times higher in the green kingfishers from the Teles Pires River compared to the Juruena River; the same results were found for the fish specimens. Fifty-eight per cent of the feather samples from the Juruena River and 90% from the Teles Pires River had total mercury concentrations above 5 µg/g, a level previously associated with adverse effects related to bird breeding. The methylmercury concentration was lowest in the liver, followed by feathers and highest in muscle. Although Juruena River bird feathers had a lower total mercury concentration, > 96% of the total mercury was methylmercury, the highest amount for specimens from both rivers. Although the concentration of Hg in the muscle of the green kingfisher is higher when compared to the feather and liver, the non-invasive monitoring through analysis of samples of feathers is an efficient biomonitoring tool for evaluation of mercury contamination in tropical birds.
Assuntos
Mercúrio , Compostos de Metilmercúrio , Animais , Mercúrio/análise , Espécies Sentinelas , Monitoramento Ambiental , Aves , Peixes , Plumas/químicaRESUMO
Mining industry is increasing the concentrations of heavy metals in coastal ecosystems of northern Chile. The presence of plastic in the nests of red-legged cormorants could be acting as a vector of metal presence in their organism. Here we analyze the source of plastic in the nests of cormorants by characterizing the abundance and type of marine debris in beaches and sea surface and the concentrations of eight metals in their feathers. Plastic was present in overall sampled nests and floating and beach debris are not the main sources of plastic to the nests. Overall analyzed metals were present in the cormorants in the following order: Zn > Cu > Se > Pb > Cd > As > Hg > Cr and Se, Cd and Pb concentrations were above the toxic limit. Further studies should investigate the potential adverse effects that plastics and metals presence may cause in this nesting colony.
Assuntos
Ecossistema , Metais Pesados , Animais , Chile , Plumas/química , Plásticos , Cádmio , Chumbo , Monitoramento Ambiental , Metais Pesados/análise , AvesRESUMO
Molting is an important process in which old and worn feathers are exchanged for new ones. Plumage color is determined by pigments such as carotenes, melanin and by the ultrastructure of the feather. The importance of plumage coloration has been widely studied in different groups of birds, generally at a particular time of the year. However, plumage coloration is not static and few studies have addressed the change in plumage color over time and its relationship to reproductive tasks. The Eared Dove (Zenaida auriculata, Des Murs, 1847) has a melanistic coloration with sexual dichromatism in different body regions. The Eared Dove´s crown is the most exposed body region during the bowing display. Our objective was therefore to accurately determine the molting period of the crown feathers and study the seasonal variation in their coloration in females and males. Our findings indicate a molting period of 6 months (January to June). The new feathers are undergoing changes in their coloration from July to December. During that period we apply an avian vision model then enabled us to reveal a seasonal variation in the coloration of the crown feathers in both sexes, as given by a change in the chromatic distances. The highest values in the chromatic distances towards the reproductive period are given by a change in the UV-violet component of the spectrum, indicating changes in the microstructure of the feather. This change in crown coloration towards the breeding season could be linked to reproductive behaviors.
Assuntos
Columbidae , Muda , Animais , Masculino , Feminino , Estações do Ano , Pigmentação , Melaninas/análise , Plumas/química , CorRESUMO
This systematic review presents the potential of using feather waste as a ß-keratin source, including the Brazilian scenario in the generation of this byproduct. The structure and properties of α- and ß-keratin, the methods commonly reported to extract keratin from poultry feathers, and applications of feather keratin-based materials are also covered in this review. The literature search for poultry production data in Brazil was conducted for the last 2 years, for the period 2021-2022. A broad literature search for extraction methods and applications of feather keratin was done for the period 2001-2022. The poultry industry is one of the largest sectors of the food industry, and Brazil was the third-largest world producer of chicken meat with more than six billion chickens slaughtered in 2021. Poultry feathers constitute about 7% weight of broilers; thus, it can be estimated that about one million tons of poultry feathers were generated in Brazil in 2021, and the improper disposal of this byproduct contributes to environmental problems and disease transmission. The most common method of reusing feathers is the production of feather meal. From economic and environmental points of view, it is advantageous to develop processes to add value to this byproduct, including the extraction of keratin. Among natural biodegradable polymers, keratin-based materials have revolutionized the field of biomaterials due to their biocompatibility and biodegradability, allowing their application in biomedical, pharmaceutical, chemical, and engineering areas.
Assuntos
Plumas , beta-Queratinas , Animais , Plumas/química , Queratinas , beta-Queratinas/análise , Galinhas , Brasil , Aves DomésticasRESUMO
Penguins are sentinel species for marine pollution, but their role as potential biovectors of REEs or TEs to ecosystems has been poorly studied. The present study analyzed (ICP-MS) feathers of young and adult Gentoo penguins from Fildes Bay, for 63 elements (including 15 REEs). Most of the REEs were present at very low levels, ranging from 0.002 (Lu) to 0.452 (Sm) µg g-1 d.w., several orders of magnitude lower than TEs. The content of TEs varied widely, with Al, Fe, Zn, Sr, Ba, Ti and Mn as the seven having the highest concentrations in the feathers of both age groups. The results show that P. papua deposits REEs and TEs through the feathers on the penguin rockery, whose potential actual impacts and long-term fate in remote regions need deeper research. This work presents essential baseline data that will be useful for further studies on Antarctic penguins.
Assuntos
Metais Terras Raras , Spheniscidae , Oligoelementos , Animais , Oligoelementos/análise , Regiões Antárticas , Plumas/química , EcossistemaRESUMO
Bird species have been widely used as suitable bioindicators of environmental mercury (Hg). However, there is still some debate about the most suitable tissue to indicate Hg body burden in birds. For a long time, blood and feathers have proved to be relevant to monitor Hg at different time scales, and recently, bill sheath has been suggested as a potential tissue to this end. In the present study, we evaluated THg in muscle, liver, feathers, claws, and bill sheath in two waterbird species (i.e. the ringed and the Amazon kingfishers) from the Teles Pires, Juruena and Paraguay rivers. Considering all species and sites, feathers (5.47 ± 2.15 µg/g) and bill sheath (3.39 ± 1.37 µg/g) had mean THg concentrations about 2-, 3- and 10-times higher than claws, liver and muscle, respectively. When bird species were segregated, the ringed kingfisher showed THg values 1.8 times higher than the Amazon kingfisher in all tissues. Moreover, results showed that the Amazon kingfisher from the Juruena and Teles Pires rivers was clearly separated from the Paraguay River (control site), and was associated with higher THg values in the claws and feathers. Results obtained for the THg concentrations in bill sheath, muscle and liver tissues of the Amazon kingfisher using multivariate analysis of canonical variates (CVA) showed a pattern of segregation between the sampling areas, being the highest THg values in Teles Pires River samples. The largest bill sheath vector in the CVA suggests that this tissue is a key variable in the segregation of the samples. Overall, feathers may be useful for effects monitoring or spatial patterns, whereas bill sheath, which are more invasive, may be advantejous for temporal trends and retrospective studies of Hg pollution.
Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Mercúrio/análise , Monitoramento Ambiental , Monitoramento Biológico , Estudos Retrospectivos , Aves , Poluentes Químicos da Água/análise , PlumasRESUMO
Growth pattern is essential for economically efficient poultry production. In this study, we aimed to describe the growth curve of chickens of the Canela-Preta breed reared in two different rearing systems, considering their different plumage colors. Initially, 204 one-day-old male and female chicks were randomly distributed in confinement and semi-confinement (102 animals in each system) without separation by gender. The animals were individually identified by wing and foot plastic brands and were weighted every seven days. The body weight and age records were used to estimate the growth curves of the following factors using the Richards model: plumage color, gender, and rearing system. The likelihood ratio test was used to verify the equality of parameters and identify nonlinear models to compare the growth patterns of the evaluated groups. The growth pattern of Canela-Preta chickens changed as a function of gender, plumage color, and rearing system. Females with black plumage, black and gold hens, and males with black and white plumage showed greater sensitivity to changes in rearing systems. Within-breed selection strategies for specific colors can improve the use of growth pattern differences, improving production efficiency. Semi-confinement is suitable for rearing Canela-Preta chickens with any plumage color, as these animals meet the free-range poultry niche market requirements.(AU)
Assuntos
Animais , Galinhas/crescimento & desenvolvimento , Plumas/fisiologia , Dinâmica não LinearRESUMO
MC1R plays a crucial role in controlling the type of melanin synthesized in the melanocytes, which greatly affects plumage color in birds. One g.16796362G/T SNP was found in the MC1R gene coding region, which caused a Met120Ile mutation in the amino acid sequence. The Met120Ile mutation was located in the third transmembrane domain of the MC1R protein and decreased protein stability. The g.16796362G/T locus achieved medium polymorphism and had significant association with feather melanin content in Chinese yellow quails. The contents of total melanin and pheomelanin with AA genotype were significant lower than those with AB or BB genotypes in skin tissues, while the expression levels of MC1R mRNA had no significant difference in feathers with different genotypes. This experiment indicated that the Met120Ile mutation could affect the function of the MC1R protein and change the biosynthesis of melanin in Chinese yellow quails.(AU)